r-磁回転超新星からのプロセス要素
D Yong1,2, C Kobayashi3,4, G S Da Costa5,3
1Research School of Astronomy and Astrophysics, Australian National University, Canberra, Australian Capital Territory, Australia. david.yong@anu.edu.au.
Nature
|July 8, 2021
まとめ
磁回転型超新星は ニュートロン星の融合だけでなく 初期の宇宙で重元素を 作り出した可能性もあります 原始的な星を研究することで これらの重要な宇宙元素の工場と ガンマ線爆発との関連が明らかになります
科学分野:
- 天文学と天体物理学
- 核天体物理学
- 宇宙化学
背景:
- 中性子星の融合は,迅速な中性子捕獲 (rプロセス) 要素の生産のための確認されたサイトです.
- 銀河の化学進化モデルは,中性子星の融合だけでは,金属に乏しい星の観測された元素の豊富さを説明できないことを示しています.
- 化学的に原始的な銀河の星は 初期の核合成のサインを保存し,未知のr-プロセスサイトへのヒントを提供します.
研究 の 目的:
- r-プロセス核合成のための潜在的な代替サイトを調査する.
- 極めて金属が少ない星SMSS J200322.54-114203.3の元素濃度パターンを分析する.
- 観測された量と異なる天体物理現象から得られた理論的な量とを比較する.
主な方法:
- 極度に金属が少ない星SMSS J200322.54-114203.3のスペクトル解析
- rプロセスの要素に焦点を当てた元素の多量パターンの測定.
- 25太陽質量の磁回転型超新星モデルから得られた核合成値と観測された豊富なパターンの比較.
主要な成果:
- 恒星SMSS J200322.54-114203.3は,非常に低い金属度でrプロセスの要素を大幅に強化しています.
- 観測された元素の豊富なパターンは,1つの25太陽質量磁回転超新星からの予測された出産と密接に一致します.
- この超新星モデルは,rプロセス,光,鉄ピーク元素の生成を説明する.
結論:
- 磁回転型超新星は,初期の宇宙における r-プロセス核合成の有効かつ重要な場所である.
- これらの超新星は,金属に乏しい星における観測された豊富さのパターンを説明し,中性子星融合のみのモデルの限界を解決する.
- ハイパーノワと長時間のガンマ線爆発の関連は これらの爆発的な出来事が 初期の銀河化学的濃縮において重要であったことを示唆しています
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